What is New in IPC-7351C.pdf - 第27页

PC B L ibr ar i es Pr e s ents : Wh at is N ew i n IPC- 7351C • L oc a l Fi duc i al s ha v e been us ed only on fine pitc h Q FP a nd B GA L and P attern s • Fi ne pi tch QFP = Less th a n 25 m i l (0.6 35 mm) p itch • …

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PCB Libraries Presents:
What is New in IPC-7351C
Snap Grid & Feature Round-off 0.01 mm
Footprint Features in 0.01 mm increments
*Japanese 80% rule
0.01
0.01
0.01
0.005 for 0.65 pitch
0.01
0.01
0.01
0.01
0.01
0.01
0.01
Line Widths
0.01
Corner Radius
0.01
PCB Libraries Presents:
What is New in IPC-7351C
• Local Fiducials have been used only on fine pitch QFP and BGA
Land Patterns
• Fine pitch QFP = Less than 25 mil (0.635 mm) pitch
• Fine pitch BGA = Less than 32 mil (0.8 mm) pitch
• Future Local Fiducial sizes will be:
• Level A (Most) = 40 mil (1.0 mm) with 80 mil (2.0 mm) solder mask & keep-out
• Level B (Nominal) = 30 mil (0.75 mm) with 60 (1.5 mm) solder mask & keep-out
• Level C (Least) = 20 mil (0.5 mm) with 40 mil (1.0 mm) solder mask & keep-out
3-Tier Local Fiducials
PCB Libraries Presents:
What is New in IPC-7351C
Zero Orientation with Pin 1 in Upper Left Corner Introduced
in 2007 in the IPC-7351A Publication – IPC-7351C “Level A”
Zero Orientation with Pin 1 in Lower Left Corner Introduced
in 2009 in the IEC 61188-7 publication – IPC-7351C “Level B”
Zero Component Orientation – Levels A & B